Termination of Contract due to Expired Pass

Retrenchment (and the associated benefits) accrue when the employer wants to terminate you.
I assume this is not the case, as they actually wanted to renew your pass and keep you as employee.
But check your employment contract for the exact wording!

Most companies don’t have any verbiage around severance/ retrenchment etc on your employment contract as it is a liability, also as Beppi mentioned, in your case employer wants to renew but MoM isn’t approving, so don’t think you would get anything at all.

I have been in a similar situation before. My EP couldn't get renewed and expired. You can negotiate with your employer to receive your notice paid in cash if they did not terminate you yet. That is because, in most contracts, you or your employer need to give a certain notice or pay in lieu of serving notice, regardless of your visa status. I managed to get one month of salary (as per my notice period) and one month of salary in compensation (after negotiating, but this is up to the employer). You should also be able to encash all your remaining leave.

Imnewhere: It's certainly a good idea to negotiate with the employer about something like this. But keep in mind that it's entirely goodwill on their part: Once you have no work pass, your employment contract is null and void (by law!) and you are not legally entitled to any more benefits arising from it.